Portugal’s prime minister has called on the emergency services to explain their response to the country’s worst wildfire as public anger mounts over the tragedy. At least 64 people have been killed and more than 150 injured.

On Tuesday, António Costa asked the head of the National Republican Guard why officers had not closed off the road where many of the victims burned to death as they fled the flames in their cars.

He also asked for clarification on the extent to which rescuers’ communications systems had been affected by the fire, and for more information on whether the high death toll was the result of unusual weather or problems with the response.

“Why, for how long and what impact was there on the planning, command and execution of operations if your very systems were not working? What was done to establish alternative connections?” Costa asked of the emergency services, according to the state news agency Lusa.

A day earlier, Costa had acknowledged that early efforts to alert the public had been hindered after the flames destroyed phone lines and communications towers but insisted that “nothing compromised the firefighting efforts”.

The prime minister’s calls came as firefighters battling the blaze said they hoped to bring it under control within 24 hours.

More than 1,100 firefighters are still tackling the fire, which is thought to have started after lightning struck a tree in the central municipality of Pedrógão Grande on Saturday.

Many are focusing on the authorities’ failure to close down the N236 road – and why it had apparently been signalled as an alternative route after a nearby road had been sealed off.

Forty-seven of the 64 forest fire victims died on the N236, which has been called the “road of death” or the “road of hell” by the local media. Thirty of them burned to death in their cars, trapped by the flames, while others died after abandoning their vehicles.

A survivor told Portuguese television that gendarmes directed them to the N236 as an alternative to the nearby IC8 route which had been closed and which the gendarmes used themselves.

“When we arrived at the IC8, they told us we couldn’t pass and directed us towards the N236. We thought that the road was safe but it wasn’t,” a survivor, Maria de Fatima, told AFP.

Among those killed as they fled was a four-year-old boy whose parents had left him with his uncle and aunt as they went on their honeymoon. According to the Correio da Manhã newspaper, his mother appealed for help on social media while his grandmother left Lisbon to try to find him. His body and that of his uncle were later found beside a car.

Assunção Cristas, the leader of the centre-right CDS-PP opposition party, said that while the country was still in mourning, a time would come “when all questions will be asked” in parliament.

Many people believe poor forest management – combined with the depopulation of rural villages, which has left many wooded areas untended – have played a part in the disaster.

“This was a unique event in terms of the impact it had on people and fatalities,” he said. “It was a bit early for this kind of fire, but we’ve had a somewhat dry winter and spring and then this heatwave, which has combined with very extreme atmospheric instability to bring lightning but no rain in the affected region.

“The area is heavily forested and when you have naturally ignited fires, they tend to occur randomly in the landscape and often in more remote locations.”

A burnt-out tractor near Castanheira de Pera. Photograph: Miguel Vidal/Reuters

Fernandes said people may have panicked when firefighters failed to appear and decided to get into their cars rather than staying in their homes.

He added that while forest fires in 2003 and 2005 had led to improvements and innovations in disaster planning, the emphasis still remained on fighting fires rather than preventing them.

A Portuguese environmental lobby group, Quercus, said the fires were the result of “forest management errors and bad political decisions” by governments over recent decades.

Quercus argued that much of the danger came from the highly flammable eucalyptus trees that have outstripped pine and cork oak to become the country’s dominant forest species and now occupy a “scandalous” area of about 9,000 sq km (3,500 sq miles).

However, Fernandes said the risk of eucalyptus had been overstated.

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“It’s a popular perception,” he said. “But it’s quite exaggerated because when we analyse fire data versus land cover data, we really don’t find fire has a preference for eucalyptus forests. It’s true it’s quite flammable, but pine forests are quite flammable and shrubland is highly flammable. Most of our Mediterranean vegetation types burn quite well.”

Three months ago the government announced new measures to combat wildfires, including restrictions on plantations of eucalyptuses and a simplified and cheaper programme of property registration to determine which land is being neglected.

However, not all of the reforms have come into legal force.

Xavier Viegas, an expert on forest fires, said while the fire had outpaced firefighters in some villages, the deaths had mainly highlighted communication problems when it came to evacuating people.

“It’s still hard to identify what failed, but it’s a bit of everything,” Viegas told Reuters.

Other countries prone to forest fires have systems in place to alert people to danger. After the fires that killed 173 people in 2009, Australia began using text messages and emergency broadcasts to get the word out.

“There’s an urgent need to organise that kind of alerting,” Viegas said. “Here, at best, someone from the parish council goes knocking on doors telling people to leave.”